Map and level design is the defining factor for many games, and it's easy to understand why: the way a space of play is designed, and how players move through it, has a profound effect on countless game systems, and ultimately, the player's experience.

For Brendan "Playerunknown" Greene, the creator of Battlegrounds, the vision for his game world was born from extensive experience creating and manipulating environments that direct players to play his games the way he intends them to be played.

“Battlegrounds is a distillation of my work in the ARMA series,” Greene says. “Building an open world that was suitable for 'battle royale' gameplay from scratch -- and doing it fast, based on iteration -- was the biggest challenge for us in terms of design, tech, and art."

A wide-open map with interesting restrictions

That circle gets smaller and smaller as time goes on

Greene created the Battle Royale mod made for DayZ that was later incorporated into H1Z1 before striking out to create his own full-fledged game, with help from South Korean developer Bluehole.

If the survival-oriented DayZ plays like a marathon, Battlegrounds feels more like a sprint. Prior to the start of a match, up to 100 players congregate in a staging area, where they can hear one another speak, and generally run around and goof off with no real repercussions as they wait for the match to start.

Next, all 100 players are placed "inside" a cargo jet, which flies over a massive hand-designed map that has various microenvironments, from rolling hills to open farm fields, forests, dilapidated towns and marshes. It's up to the players which area they want to parachute into -- it's a crucial decision right at the start of the round that can separate winners from losers: Urban areas offer more weapons, armor, and supplies, but are typically dangerous, early-game warzones. Remote areas are short on supplies, but can offer less competition.

"The world’s overall density is designed to have different buildings or environmental characteristics to keep players engaged in the game before they get frustrated or bored, no matter which direction they choose to go."

Aside from environments and the placement of supplies, there are other motivations that Greene and his team designed into the game to keep players moving in interesting ways. Shifting red zones, where planes drop bombs, dislodge campers. Engine sounds, and fine-tuned shooting sound characteristics such as attenuation, occlusion, obstruction, and reverb allow players to predict where risks (or potential targets) are located.

All these pieces of design discourage players from getting too comfortable on Battleground's maps, as sprawling as they are. But it's the heavy hand of the designer that really begins to crank up the sense of urgency and danger.

“And then there is the ‘blue wall,’ the deus ex machina of our game,” says Greene. As a match goes on, the circumference of the play area decreases. The constricting play area forces players to come closer together, increasing the chance of engagements. This is seen from the player-level as a blue wall, and if you're on the wrong side of that wall, you're dead.

“Players need to move on the map constantly; they cannot relax even just for a moment or they risk being killed," Greene explains. "The world’s overall density is designed to have different buildings or environmental characteristics to keep players engaged in the game before they get frustrated or bored, no matter which direction they choose to go.”

On-the-fly playtesting and map iteration

"After working in the ARMA universe for the past four years, and choosing a range of new maps to add to the mod, I found that island maps worked better for these games," he says. "I created a fictional history so the art team could better create a concept, and found an island setting would fit that history and allow for the ability to use boats.” It was important to Greene to give players more traversal options for crossing and exploring the map.

Once he had the idea of an isolated island in mind, with all of its defined limits and dimensions, Greene began envisioning the elements that would fill it out. “I have always had a love of the brutalist architectural style found during the Soviet era during the 1950s," he says. "We built island terrain based on simple sketches that I created, and then deployed trees and grass on the terrain. We also placed buildings with the item spawn system as well as walls with holes that players can use to get in and out.”

"In many ways it felt like a live game development jam session -- way more interesting than sitting in a meeting room and discussing hypotheticals."

For Greene and his team, it wasn’t a matter of lengthy meetings spent hammering out design elements and workshopping ideas. Instead, they dove straight into creating content, and then iterated on existing assets as they went. The raw material was introduced, and then refined on-the-fly through playtesting and implementing new ideas.

“In many ways it felt like a live game development jam session -- way more interesting than sitting in a meeting room and discussing hypotheticals," he adds. "All the team playtested the game hundreds of times throughout development. We began as a small team of 20 people, but for each and every round, we all played to win, not to test. That feedback is reflected in every detail of our world.”

Building a large play area like the one in Battlegrounds was a process of creating it piece by piece. Standard shooter design philosophies helped for smaller chunks, while larger areas were designed with battle royale gameplay in mind. Filling out these areas became a strategic consideration.

“While our game has many places to hide, they are not entirely secure," he says. "For example, camping out behind big windows provides protection while taking out foes, but on the flipside, you risk exposing your location to skillful players.”

You are now free to leap out of the cabin

Greene says this process meant constant tuning and lots of little adjustments. “Our work was very focused on designing context rather than levels," he says. "Not only did we adjust item spawns, but also made changes to things like the capacity value for individual items, vehicle driving characteristics, and swimming speed.

But there have also been larger, more sweeping changes that diverged from Greene's original design.

“The map design has changed somewhat from my initial sketches. The main changes were the addition of new areas, new POIs [points of interest], and adding a river to the main island to allow players to use boats in the interior," he says. "Each of these POIs and new areas were added to give a wider range of environments for players to explore and fight within.

"When creating the map, our goal was to make each match feel different. Adding more environment types and locations to the map helped us achieve this.”